The Troy M14 MCS will work with all Springfield M1A rifles except ones that feature a rear lugged receiver. The Troy M14 BattleRail however will work with all models including ones that feature a rear lugged receiver.

No, currently Troy does not produce a .308 handguard that is compatible with the RRA .308 platform. RRA uses a different thread pitch and length on their receivers that greatly differs from the Armalite and DPMS rifle systems.